Hi! I'm dealing with this problem that seems to be very easy, however the teacher says I'm wrong, and I don't know where's my mistake (She didn't tell me). So I hope you can tell me where did I go wrong

Here's the problem:

A falling sky diver travels 64m in 2 seconds. How much will he travel in 8 seconds? (Ignore the air resistance)

My solution:

I used the equation y=y

o+v

ot+1/2gt

^2
with

y=64m

y

0=0m

g=9.8 m/s

^2

t=2s

Then I solved it for vo, obtaining vo=22.2 m/s. And finally obtained:

y=(22.2)(8)+1/2g(8)^2=491.2 m

I don't know what did I do wrong, and the teacher didn't even tell me what was the right answer. I hope you guys help me figure it out. Thanks!